This invention is directed to the art of printing and, more particularly, to a press makeready system.
The invention will be described in conjunction with making ready a web fed newspaper or other commercial press having several printing units; although, it is to be appreciated that the invention may be employed in making ready various other types of printing units.
The production of a newspaper, magazine, book, periodical, or any type of publication requires a makeready operation during which the various printing units are prepared for a subsequent run operation. Among the various steps involved includes webbing the press and positioning the various printing plates on the correct plate cylinders. The determination as to how the press is to be webbed and which printing plates are to be placed on which plate cylinders is a laborious time consuming procedure, detracting from the productivity of the press.
In order to facilitate an understanding of the background of the invention, reference is made to the schematic illustration of a press in FIG. 1. This press has seven printing units 10, 12, 14, 16, 18, 20 and 22. This description outlines a newpaper press arrangement. However, this invention can apply to any other type of commercial or publication press. Press units 10 through 16 are located to the left of a folder 24. Webs on press units 10 through 16 move to the right from the press units to the folder and the webs on the three units to the right of the folder move toward the left to the folder. In common terminology, the units designated as right hand or left hand depend upon the direction of movement of the web to the folder as viewed from the workside of the press. Accordingly then, units 10 through 16 are termed right hand units and units 18 through 22 are termed left hand units.
In the illustrated press arrangement, six webs are handled by the press. These are webs W1 through W6 which are webbed through the various press units, as shown. Each press unit has two plate cylinders which are adapted to receive the page printing plates for four pages of printing across the width of the press with each plate cylinder accommodating two page sets of plates around the periphery of the cylinder. The printing units illustrated have upper and lower plate cylinders so as to be capable of printing on both sides of the web. For example, press unit 10 includes upper and lower plate cylinders 30 and 32, each of which is adapted to carry printing plates. The web can be passed between two blanket cylinders 34 and 36 respectively associated with plate cylinders 30 and 32. A web passing between blanket cylinders 34 and 36 may be printed simultaneously on the top and bottom sides of the web. This then provides two printing couples. Also, a web may be passed between blanket cylinder-plate cylinder pair and then through the blanket to blanket pair and this also provides two printing couples. Printing units 10, 14, 18 and 22 all take the form as shown with respect to printing unit 10. However, printing units 12, 16, and 18 are provided with an additional capability in the form of a half deck. Half decks 40, 42 and 44 are carried on printing units 12, 16 and 20, respectively. A half deck serves to print on only one side of the web to provide one printing couple. As shown with reference to printing unit 12, a half deck includes a plate cylinder 46 which is adapted to carry printing plates together with an impression cylinder 48. The impression cylinder serves as a backing for the printing operation as the web passes between the plate cylinder and the associated impression cylinder.
Consequently then, a printing unit such as unit 10 can be used to print on two sides of a single web or to make two different printings on a single side of one web, whereas the printing unit having a half deck such as printing unit 12 can also provide an additional printing on one side of a web. Half decks are arranged so that the webbing may be passed either in the direction toward the folder or away from the folder, as indicated by the examples with reference to printing units 12 and 20.
As is well known in the art, during the printing of a newpaper, the web will be severed into ribbons so as to provide ribbons which are two pages wide for folding and assembly purposes. Each ribbon will ultimately be severed into sections of two pages wide with a fold to provide a one page wide newpaper. In a simple four page newpaper, the complete newspaper would be printed by printing pages 1 and 4 on one side of the web on one plate cylinder and pages 2 and 3 on the opposite side of the web. This requires in the press configuration illustrated in FIG. 1 only a single half web with only one printing unit which would simultaneously print on opposite sides of the web. The printing plates for pages 1 and 4 might be located on the upper plate cylinder in a blanket to blanket configuration and the printing plates for pages 3 and 4 may be on the lower plate cylinder. However, as additional pages are to be printed for the newpaper, or a newspaper section, additional webs (or half webs) may be required and additional printing units may be required. For example, when printing an 8 page newpaper section, the plates in a blanket to blanket printing configuration would have the printing plates for pages 1 and 8 adjacent to each other on one side of the web on the upper plate cylinder and the plates for pages 2 and 7 would be adjacent to each other on the other side of the web on the lower plate cylinder. This defines a sheet having two pages on each side which is folded and will have inserted into it to achieve the 8 page newspaper, a second ribbon (half web) which has pages 3 and 6 adjacent to each other on the top side of the second web and pages 4 and 5 adjacent to each other on the bottom side of the second web. When this two page wide second ribbon is severed and folded into the section containing pages 1, 2, 7 and 8, all the pages will be in succession.
From this simplified explanation, it can be seen that as the number of pages in a section increases, the location of the printing plates and the number of webs required becomes more complicated. This provides difficulties in properly locating the page plates on the proper printing cylinders and in the proper position on the printing cylinders of the proper printing units to assure that the webs can be lead to the folder so that the sections may be properly assembled.
The webbing of the press and the correct location of the printing plates is further complicated when certain pages of a section are to have color different from the color for the remainder of the newspaper. For example, newspapers are customarily printed in black ink. If a color is to be added to the page containing black ink, then that page requires that a printing couple be dedicated to that color. Thus, if four colors are to be printed then four printing units, in the blanket to blanket configuration, will be required. This is true even if four different colors are to be printed on four different pages. Consequently then, when color (in addition to black ink) is to be printed on different pages, it will facilitate webbing the press if the color appears on the pages which would normally be associated with each other, and as we have already seen, associated pages will depend on the total number of pages to be printed for each newspaper section.
Fron the foregoing, it can be seen that the web layout pattern as well as the positioning of the printing plates on the various printing units for a given press description (configuration) and preferred mode of operation will be dependent upon the number of sections to be printed, the number of pages in each section, and which pages in each section are to be printed in color. The press description is usually fixed for a press installation. This would include the number and location of the printing units, the number and location of half decks, the number of formers, and their location, the number of four color units, the number and location of angle bar sections, the number and location of bay window arrangements, and whether or not double delivery or single delivery is to be employed. The preference description is usually fixed for a printer and this would include whether the operation is to be run without quarter webs and what the run mode shuld be (straight or collect). The various jobs will cause variations in webbing and plate location dependent upon the variables: number of sections, pages per section and color information.